Current count, from CMTS initialization, of contention request
data minislots utilized on this upstream logical channel. This
includes all contention minislots for IUC2 applicable to bursts
that the CMTS correctly received.
This is the 64 bit version of docsIfCmtsUpChnlCtrUsedCntnReqDataMslots,
and will not be accessible to SNMPv1 managers.
Support for this object is optional. If the object is not supported,
A value of zero is returned.